Packaging machine



INVENTOR.

Dec. 5, 1961 F. J. PANCRATZ PACKAGING MACHINE 3 Sheets-Sheet 1 Filed Oct. 5, 1956 Dec. 5, 1961 F. J. PANCRATZ 3,011,294

PACKAGING MACHINE Filed Oct. 5, 1956 5 Sheets-Sheet 2 Frank J. Pancraiz INVENTOR.

Dec. 5, 1961 F. J. PANCRATZ PACKAGING MACHINE 3 Sheets-Sheet 3 Filed Oct. 5, 1956 I lrlllllllllllllr!llillr Frank J. Pancratz INVENTOR.

BY aQmaml 2? 72%,

United States Patent 3,011,294 PACKAGING MACHINE Frank J. Pancratz, 924 S. Washington St., Park Ridge, Ili. Filed Oct. 5, 1956, Ser. No. 614,120

14 Claims. (Cl. 53-112) This invention relates to a packaging machine, and, more particularly to a packaging machine capable of encasing goods between two parallel webs of heat sealable material.

The type of packaging to which my machine is particularly suited is the flexible, transparent wrap commonly provided food goods such as wieners, bacon, or other means; coffee, powdered goods, etc. It is important in such a machine that the operation be virtually automatic since the profit margins on the goods wrapped do not permit substantial expenditures for such operation. The machine must also be rapid in operation in comparison to its cost in order to justify its adoption. Further, the machine must be capable of evacuating the package since many of the foregoing goods must be provided in air-free packages.

It is therefore an object of my invention to provide an automatic, relatively inexpensive packaging machine capable of packaging goods between parallel webs of a heat-scalable material. Another object of-my invention is to provide a packaging machine capable of providing an evacuated package. Other objects and advantages of my invention will appear as the specification proceeds.

The packaging machine of my invention includes a moving carriage having a set of dies, the dies being movable into clamping engagement so that work or goods between the dies can be packaged during carriage movement. Carriage movement unwinds rolls of packaging material to provide webs which are formed into a package encasing the product. My invention also includes a new clamping and evacuating arrangement for goods to be packaged between two parallel webs of packaging material.

My invention will be explained in conjunction with the accompanying drawing in which FIG. 1 is an elevational view partially in section of my packaging machine; FIG. 2 is a fragmentary plan View; FIGS. 3, 4 and 5 are schematic elevational views of the machine of my invention showing various positions of the movable carriage; FIG. 6 is a cross-sectional view taken along the line 66 of FIG. 2; FIG. 7 is a cross-sectional view taken along the lines 7-7 of FIG. 2; and FIG. 8 is a detailed cross-sectional view taken along the lines 8-8 of FIG. 2.

Referring now to the drawing, and FIG. 1 in particular, the machine of my invention is provided with a frame designated generally 10, but shown only in fragmentary form so as to not encumber the drawing. Subsequently in the specification when elements are referred to as associated with the frame, it is to be understood that the frame can be provided in a form consistent with acknowledged machine design or the elements disposed on independent frames but in the indicated spaced relation. Frame 10 is provided with a pair of guides or tracks 11 extending longitudinally thereof. Slidably mounted on tracks 11 is carriage 12, Carriage 12 includes two heads supported on a set of dies and mated with leader pins or guides as can be appreciated from a consideration of FIG. 2 wherein one-half of the machine is shown in considerable detail while the other half is shown in fragmentary form. The upper die or platen is designated 12a,

while the lower die, which provides the sliding surface borne by tracks 11, is designated 12b. Upper paper web 13a and lower paper web 13b issue from rolls (not shown 3,011,294 Patented D ec.'5, 196.1

to provide a length of horizontal travel for web 13b not in contact with web 13a whereby a platform for the next batch of goods is provided as designated at 16. In this description the term forward is used to designate motion away from the feed end and toward the discharge end of the machine while the reverse motion is indicated return, both terms referring to the movement of carriage 12. I 7

Lower die 12b of carriage 12 is provided with a feed end pedestal 17 and a discharge and endpedestal .18. Pedestals 17 and 18 provide anvils or contact surfaces for the elements of upper die 12a which perform the functions of clamping webs 13a and 13b together and heat-sealing the webs together. Mounted on die 12b between spaced pedestals 17 and 18 is pressure plate 19 which can be seen in enlarged form in FIG. 6. Pressure plate 19 is secured to lower die 1215 by suitable guide bolts in combination with springs 20. When upper die 12a is spaced from lower die 12b, as can be appreciated from a consideration of FIG. 5, springs 20 urge'pressur'e plate 19 upward into coplanar relationship with thefltops of pedestals 17 and 18. 1

i The lateral arrangements of my' machine can be ap-- preciated from a consideration of FIG. 6 wherein the upper and lower portions of carriage 12 extend across the width of the machine while the width of lower pressure plate 19 is slightly less than that of the web used to encase the goods.

Still referring to FIG. 6, it is to be seen that longitudinally disposed pedestals 21 (not shown in FIG. 1) provide anvils for clamping and heat-sealing the sides of the webs enclosing goods 15. i

The upper die 12a of carriage 12 is similar in arrange-- ment to lower die 12!), having upper pressure plate 19a secured thereto by suitable bolts and springs 20a. Pro,- vided along the longitudinal sides of upper die 12a are clamping and heat-sealing elements 22, Elements 22 are rigidly secured to upper die 12a and contact pedestals 21 when upper die 12a.is unsupported, as on the forwardmotion of carriage 12. During such motion, lower pres-. sure plate 19 and upper pressln'e plate 19a compress webs 13a. and 13b against goods 15.

Also rigidly secured to upper die 12a is discharge end clamping element 23 and discharge end heat-sealing element 23a, both of which extend athwart or transverse of, each head. For the feed end of carriage 12, I also provide separate clamping and heat-sealing elements. As in the case of discharge end clamping element 23, feed end clamping element 24 extends the width of each head and is rigidly secured to upper die 1211. Feed end heatsealing element 25 is slidably mounted on upper die 12a. Clamping element 24 is tipped with a length of rubber cord or tube stock 24a which is the portion of 24 contacting pedestal 17. Pedestal 17 is provided with a corresponding rubber insert 17a. This permits tight clamping of any inserted webs along with mean for evacuating the interior of a package such as shown in FIG. 7.

Pedestal 17 is also provided with a transverse block 25a containing a V-groove which corresponds to the line of contact with the tip of heat-sealing element 25. Such a mating structure I have found effective for heat-sealing I such laminated webs as polyethylene and cellulose. Providing block 25:: permits ready exchange with other blocks having grooving suitable for establishing greater or smaller breadth of contact consistent with the type of film to be heat-sealed.

Upper die 12a is provided with an upwardly extending end plate 26 which extends across the width of my machine and provides one bearing surface for the vertical sliding motion of feed end heat-sealing element 25. A continuation of that bearing surface is depending guide member 26a which extends the width of each head. Guide member 26a also functions to prevent webs 13a and 13b from contacting heat-sealing element 25 until element 25 is in depressed position. Plate 26, along with other transverse members anchors the two heads of carriage 12 together.

Feed end clamping member 24 is spaced toward the feed end from transverse member 26 and provides a second bearing surface parallel to that of plate 26 for guiding sliding heat-sealing element 25. Element 25 is arranged with a substantial shank portion narrower than its bearing portion so that spaces 25b adjoining the heated element 25' provide air space heat insulation.

The purpose of providing separate clamping and heatsealing elements at the feed end of my carriage can be appreciated when it is understood that my machine can be particularly adapted to heat-sealing an evacuated package. For this purpose an evacuating line or tubular conduit 27 (shown in fragmentary form in FIG. 2) is provided on carriage 12 and extending parallel to tracks 11, being located between the travel of webs 13a and 13b, terminating just rearward (toward the discharge end) of clamping member 24. Conduit 27 is connected to a vacuum pump (not shown). A cross-sectional view of this arrangement is shown in FIG. 7. Thus, my machine permits first heat-sealing three sides of a flat enclosure while clamping the fourth or feed-end side. During the clamping action exerted on the fourth side, evacuating tube 27 may be employed to evacuate the chamber provided by three heat-sealed sides and a fourth clamped side. Once evacuation is achieved, the fourth side can be heat-sealed by element 25. Conduit 17 is operatively associated with clamping element 24, so that when upper die 12a is raised, conduit 27 is also raised, permitting movement of web 13b and goods to the position designated 15.

In order to provide a continuously operating machine, I provide a crank linkage generally designated 28 and associated with frame 10. Crank linkage 28 is secured to carriage 12 and causes carriage 12 to be reciprocated. On the forward movement of carriage 12, the upper and lower dies 12a and 12b, respectively, are in contact with each other, upper die 12a being carried by lower die 12b through heat-sealing elements 22 and 23a andclamping element 24. The contacted dies provide a rectangular chamber in the embodiment shown equipped with internal pressure plates which urge webs 13a and 13b against goods 15. Crank linkage 28, upon the return motion of carriage 12 elevates or spaces die 12a from die 12b permitting webs 13a and 13b and goods 15 to remain stationary on frame 10 while the carriage 12 is returned to a position above the next goods to be encased, designated 16 in FIG. 1. It is to be appreciated that the forward motion of carriage 12 causes webs 13a and 13b to be pulled toward the discharge end which also moves new goods 16 into the position occupied by clamped goods 15 in FIG. 1. This sequence can be appreciated from a consideration of FIGS. 3, 4 and which show upper die 12a in its two positions relative to lower die 12b. FIGS. 3 and 4 represent the beginning and middle portion of forward travel of carriage 12 when it is borne by lower die 12b. In FIG. 5, which depicts the beginning of the return movement of carriage 12, upper die 12a is spaced from lower die 12b. FIG. 4 also differs from FIG. 3 in showing heat-sealing element 25 associated with the feed end of carriage 12' in contact with pedestal 17 so that heat-sealing of the feed end of the webs enclosing goods 15 is achieved during a portion of the forward stroke of carriage 12. FIGS. 3 and 4 also differ in the position of shear blade 29. Since FIG. 3 also representsthe end of the return stroke of carriage 12 as well as the beginning of the forward stroke, it is at this point that I prefer to separate the now-enclosed goods from the continuous webs by depressing shear blade 29 against the discharge end of pedestal 18. This can be seen' also in FIG. 1. Thus, the forward motion of carriage 12 pulls webs 13a and 13b a distance just sufiicient to accommodate a subsequent package.

The crank linkage means 28 which not only reciprocates carriage 12, but 'which also actuates feed end heatsealing element 25 and shear element 29 includes lever arm 30 pivotally associated with frame 10, as at 30. Lever arm 30 is caused to move in an oscillatory motion by crank 31 mounted on shaft 32 which can be mounted on or associated with frame 10. Crank 31 is provided with pin 33 which engages slot 30a of lever arm 30 and is in sliding contact with the side walls of slot 30a. Thus, as crank 31 rotates, pin 33 rides reciprocably in slot 301: as can be appreciated from a consideration of FIGS. 3, 4 and 5. Crank 31 is so positioned with respect to lever arm 30 that two-thirds of the time required for one rotation of crank 31 is occupied in moving lever arm 30 forwardly, while only one-third of the time required for one revolution of crank 31 is required to reciprocate or move lever arm 30 in a return motion. Lever arm 31) is pivotally linked to carriage 12 through linkage 34 which connects to a second pedestal 35 on the discharge end of lower die 12b. Thus, my machine is provided with a quick return action, the return taking approximately one-half the time for the forward or operating motion of carriage 12. Thus with a shaft speed of 20 r.p.m., the machine of my invention employing two heads (or one die set with guides) produces 4.0 packages per minute.

Associated with the end of lever arm 39 opposite the end fulcrumed at pivot 30b are two longitudinally extending members which operate to elevate or space top die 12b and actuate feed end heat-sealing element 25 and shear blade 29 at the proper times in the sequence of movements of carriage 12.

One longitudinal member, designated 36 and shown in solid line in FIG. 1 is designated a support bar since it is this member that supports upper die 12a in spaced relation to lower die 12b upon return movement of carriage 12. The support of die 12a is provided through hanger 37. Hanger 37 is equipped with a roller 37a shown supported on support bar 36 in FIG. 5. Support bar 36 is pivotally supported at one end by lever member 3t) and at the other end by linkage 38 which is secured to the feed end of carriage 12. Alternatively, it is possible to support the end of support bar 36 opposite the end connected to lever arm 30 from frame 10 in suitable guide bearings.

The second longitudinal member pivotally secured to one endyof lever member 30 is shown partially in dotted line in FIG. 1 and is designated lift bar 39. Lift bar 39 is not secured at the opposite the pivotal connection with lever arm 30, but slidingly rests against carriage 12. Intermediate the ends of lift member 33 is provided lug 40 which engages cam 31a roller of crank 31 at the end of forward movement of carriage 12 as can be seen in FIG. 5. Except when actuated by cam 31a, lift bar 69 extends through slot 37b of hanger 37 which is its usual disposition except at the end of the forward stroke of carriage 12. Upon engagement of lug 40 with cam 31a, lift bar 39 is swung upwardly to the position indicated in FIG. 5, during which action it engages the upper edge of notch 37 (i.e., roller 37a) and raises hanger 37 and attached upper die 12a into spaced relationship with lower die 12b. When hanger 37 is raised a sufficient distance so that roller 37a (as can be seen best in FIG. 6) no longer bears against the side of support bar 36, spring 41 (also seen in FIG. 6) snaps hanger 37 into a vertical position so that roller 37a-rides on the top surface of support bar 36. To aid in this operation, hanger 37 is pivotally secured by means of bolt 42 to upwardly extending lugs 43 on upper die 12a.

To return upper die 12a into contact with'lower die 12b, 1 provide ntt bar 39 with sidewardly-extendi'ng boss 44. At the endof the return stroke of carriage 12, boss 44 engages hanger 37 and pivots it slightly clockwise about pivot 42 when viewed from the discharge end (as can be seen in FIG. 6 in dotted line). Roller 37a then engages a side plate or track on support bar 36, the side plate being designated 36a in FIGS. 6 and 1. Shortly before the end of the return stroke of carriage 12, roller 37a of hanger 67 reaches the sloped end of side plate 36a designated 36b in FIG. 1 and permits upper die 12a to be returned in contact with lower die 12b. To insure proper register between upper die 12a and lower die 1212, I provide a series of guide posts (not shown) on lower die 12b aligned with suitable bushings in upper die 12a. Also cooperating to align upper and lower dies 12a and 12b, respectively, and to urge the two dies together are spring-loaded bolts 45 shown in FIG. 6.

In the machine of my invention, the greater speed and distance of travel of support bar 36, as compared to carriage 12, are utilized to actuate elements responsible for sequential operations. For example, support bar 36 is provided with two depending lugs which operate to actuate the above-mentioned feed end heat-sealer element 25 and shear element 29. Feed end heat sealer element 25 is urged away from pedestal 17.by spring 46 which is end-secured to clamping element 24 and seen in FIG. 1. Feed end heat sealer element 25 is provided with roller 47 at the upper end thereof which can be engaged by lug 48 of support bar 36. Lug 48 is so designed as to depress roller 47 and, therefore, heat-sealing element 25 for about one-half of the forward stroke of carriage 12. Support bar 3-6 is provide with a second lug designated 49 which operates to depress a roller 29a secured to the end of shear blade 29, shear blade 29 being slidably mounted on upper die 12a and spring-urged away from pedestal 18 in a fashion similar to that described with respect to feed end heatsealer element 25. Lug 49 is so arranged as to. depress shear element 29 only at the completion of the return stroke of carriage 12. I

In order to maintain heat-sealed webs 13a and 13b in stationary relationship to carriage 12 and frame during the return stroke of carriage 12, I provide an ejector clamp generally designated 50 in FIG. 2 and shown in enlarged cross-sectional view in FIG. 8. Clamp 50 is not shown on the sequential views of FIGS. 3, 4 and 5, nor on FIG. 1 since it might interfere with the ready understanding of the crank lever mechanism portion of my invention which would thereby be masked by the presence of the clamp in those views. Again it is to be appreciated that my machine includes dual packaging elements, the machine being more or less symmetrical along the center line shown in FIG. 2 except for the crank linkage mechanism. Thus, my machine includes two clamps 50.

Clamp 50 includes clamping jaw members 51 and 52 as shown in FIG. 8. These jaws are ordinarily springurged together except at the end of the forward stroke of carriage 12 when lug member 53, secured to upper die 12a, engages ejector clamp 50 and separates jaw members 51 and 52. At the instant of unclamping of jaw members 51 and 52, the previously shearedpackage is dropped and the end can be conveyed away from under my machine. 13a and 13b enter between jaw members 51 and 52 to be clamped. Upper jaw 51 is secured to upper jawcollar 51a, collar 51a being secured to tube 54 which is slidably mounted in block '55 secured to frame 10. Collar 51a is urged upwardly by spring 56. The lower jaw collar 52a is floating, being mounted on block 55 by spring '58 and dowel 57, by limited in its upward travel away from block 55 by upper jaw 51. Collar 51a is limited in its'upward travel by collar 54a secured to tube 54. Thus, during the major portion of an operat- Shortly thereafter, heat-sealed webs 6 ing cycle, jaws 51 and 52 are closed by spring 56 urging upper collar 51a until limited by collar 54a while lower collar 52a is urged upwardly by spring 58.

When lug member 53 is in the position shown, it depresses pin 59 slidably mounted in tube 54. Pin 59 is provided with a transverse pin 59a which extends through a slot 54b in tube 54. Pin 59 is ordinarily urged upwardly by spring 540 mounted in the end of tube 54. Thus, when pin 59 is depressed by lug member 53, transverse pin 59a contacts the top of lower jaw collar 52a and depresses the lower jaw assembly. As pin 59 is further depressed, pin 59a reaches the end of slot 54b and causes upper jaw collar 51:: to be depressed with any further downward movement of pin 59. When pin 59 is depressed the maximum distance, jaws 51 and 52 are in proper spaced relation to each other and to frame 10 to enter slots 23b in discharge end clamping element 23. When jaws 51 and 52 are located in slots 23]), they are positioned to clamp combined webs 13a and 1317.

As lug member 53 moves forwardly, pin 59 is permitted to move upwardly through slot 53a in lug member 53. This reengages jaws 51 and 52. At about this time in the operation of my machine, upper carriage 12a is raised through the operation of lift bar 39 which, in turn, causes lug member 53 to be raised. This permits the entire ejector clamp assembly to rise until limited by collar 54a. By having ejector clampStl rise slightly during the separation of the die elements, I eliminate a strain on the end of heat sealed webs (13a and 13b) which otherwise might result in web rupture.

Inasmuch as sometimes it is deemed desirable to pro vide a heavier seal along the side of the package enclosing goods 15, I provide auxiliary presealing mechanism generally designated 60 and shown in FIG. 1. It is to be appreciated that the transverse seals for the package for goods 15 are applied in conjunction with separate clamping elements, not present along the side seals. Presealing mechanism 60 includes two pairs of heat-sealing rollers 60a and 60b, 6011 being the upper pair of heatsealing rollers and 6% the lower rollers. Upper rollers 60a are brought into engagement with lower rollers 605 only upon the return stroke of carriage 12 wherein support bar 36 actuates a rocker arm fixed to the shaft on which heat-sealing rollers 60a are also secured. Upper heat sealing rollers 60a are mounted on shaft 61 supported by arms 62 from transverse shaft 63. Fixed to transverse shaft 63 is rocker arm 64 and position arm 65.

,As shown in FIG. 1 and FIG. 3 and FIG. 4, position arm 65 is maintained in stable position by a springloaded indexing ball 66 snapped into the detent 67 of cross member 6711 secured to carriage 12. At the end of the forward stroke of carriage 12, lug 68 engages rocker arm 64 and snaps indexing ball 66 out of detent 67, the weight of roller 60:: being sufiicient to rotate arm 62 around shaft 63 and bring upper preheat-seal rollers 60a into contact with lower heat-seal rollers 60b. Inasmuch as the preheat-seal mechanism is secured to carriage 12, it is returning with carriage 12 while webs 13a and 13b are stationary. At the end of the return stroke of carriage 12, lug 69, also secured to support bar 36, engages rocker arm 64 and snaps indexing ball 66 into detent 67. The sequence of operations is also shown in FIGS. 3-5,

-wherein FIG. 5 shows the preheat-sealing rollers in contact as they are during the duration of the return stroke of carriage 12. i

.Also shown at the extreme feed end of my machine are corrugating rolls 70 and 14b. Both rolls are attached to frame 10. Roll 14b also acts as a guide roll for lower web 13b as pointed out above. The scoring or corrugating of web 13b achieved by the cooperation of rolls 70 and 14b is helpful in providing air channels for exhausting air from the heat-sealed package clamped between upper and lower dies 12a and 12b, respectively. I have found that with smooth surface thin flexible film due to atmospheric pressure the length of webs between the end of exhaust conduit 27 and the feed end of goods 15 adheres so tightly that air-cannot enter exhaust conduit 27. By providing the lower web with corrugations, I eliminate this defect. The corrugations are provided by contacting lower web 1% to a heated roll 70. Heat is produced by conventional electrical heating elements, energized by slip-rings 71 shown in FIG. 2 (the same arrangement of wiring is employed with hollow shaft 61 of the auxiliary presealing mechanism) and associated with the support assembly for roll 70. The same type of heating arrangement is employed for the pre-heat sealing roller mechanism 60. Corrugating rolls 70 (one for each head) are mounted on hollow shaft 72, shaft 72 being rotatably borne by arms 73 secured to transverse shaft 74. lAlSO fixed to shaft 74 is arm 75 which is urged in counterclockwise motion in FIG. 1 by spring 7 6 secured between the unattached end of arm 75 and frame it Also secured to the unattached end of arm 75 is longitudinal rod 75a. Opposing the counter-clockwise urging of spring 76 is lug 77 of carriage 12 which bears against collar 78 of longitudinal rod 75a. As carriage 12 moves forwardly, and lug 77 no longer bears against collar 78, spring 7 6 urges arm 75 in a counter-clockwise motion so as to bring rolls 70 and 14b into contact as shown in FIG. 4. Near the end of the forward stroke of carriage 12, lug '77 contacts a second collar 79' on rod 75a (as shown in FIG. which causes roll 7 i? to be rotated further counterclockwise and out of engagement with roll 1412. Upon the return of carriage 12, lug '77 once again engages collar 78 on rod 75a and causes roll 71 to be moved through a clockwise are back to the position indicated in FIG. 3. The various positions of roll 70 are maintained by a spring-loaded indexing ball mechanism (not shown) which is similar to that described in connection with pro-heat sealing mechanism 60. This provides a corrugation of proper length ahead of exhaust conduit 27.

In the event a powdered material is to be packaged, I have found that exhaust conduit 27 often becomes plugged with particles. For this purpose, I have provided a web screen 79 of width considerably narrower than webs 13a and 13b which is provided from a separate source roll and enters carriage 12 on the underside of upper web 13a. The web screen 79 is of scalable mate rial, perforated and roughened for powdered goods, roughened only for coarse or solid goods, thereby aiding air travel toward exhaust conduit 27 during evacuation.

Feed bar 80 is secured to support bar 36 at the end opposite the end pivoted on lever arm 3%. Feed bar 80.

carries cross bar 81 which pushes new product 16 through forming member 82 (shown in cross section in FIG. 7). Former 82 is mounted on lower carriage 12b, forward of sealing rollers 60a and 60b, consisting of spaced metal sheeting members 83 and 84. Upper web 13a is guided longitudinally between sheeting members 83 and 84 and lower web 13b over former element 82a to roller 60b and heated sealing roller 60a for pre-sealing side seams. In certain instances, side sealers 22 (FIG. 6) are not required.

Operation as the proper spaced relationship to the various moving elements of my machine is preserved.

Webs 13a and 13b from the two rolls are then threaded into my machine, web 13a contacting idler or guide roller 14a and threaded through former 82 and rollers 60a and 66b while the machine is stationary with carriage at the near end of the return stroke. The webs are then threaded between upper and lower press plates, designated 19a. and 19 respectively. Upon start-up, upper die 12a is maintained above lower die 1211 by positioning lever arm 30 so as to support-hanger 3 7 on support bar 36. The ends of webs 13a and 13b are secured within jaws 51 and 52. v

Goods such as wieners 16 are then loaded on lower web 13b, as from a conveyor travelling transverse to the travel of web 13b. The space between the two heads of my machine provides a convenient exit passage for any such conveyor.

After completion of about two-thirds of one revolution of shaft 32, goods 16 are moved into the position designated 15 in FIG. 1, web 131) being moved forwardly by the movement of carriage 12. As goods 16 are moved forwardly, cross bar 81 of feed bar pushes goods 16 into bag-forming mechanism 81 as shown in FIG. 7. When goods 16 first assumes the position designated 15, upper die 12a descends from its supported position on side plate 36a of support bar 36, proceeding down sloping edge 36b of side plate 36a. When upper die 12a is no longer supported on support bar 36, it is borne by lower die 12b, contact being established along the longitudinal edges by heat sealing and clamping elements 22, and across the sheet by clamping elements 23 and 24. The discharge edge of the sheet is also contacted by heatsealing elements 23a. Since heat-sealing elements 22 and 23a are continuously energized, as byelectricity, three sides of the package are established.

. The left hand portion of FIG. 7 shows the cross-sec- 12, lug 48 depresses heat sealer element to provide the fourth side seal on the package which has been evacuated through evacuating tube 27. As crank 31 continues its rotation and carriage 12 returns, lug 49 depresses shear blade '29, severing a pair of webs 13a and 13b previously heat-sealed together.

The left hand portion of FIG. 7 shows the crosssectional arrangement of conduit 27 at a point where conduit 27 is clamped between clamping element 24 and pedestal 17. In cross section, conduit 27 has a flat bottom surface which bears against web 13b and pedestal 17 while its upper surface approximates a sine curve with the lateral edges being quite sharp as at 27a so as to insure a leak-proof fit with clamping element 24.

As carriage 12 nearly completes its forward travel, lug member 53 engages clamp 50 and forces jaws 51 and 52 apart so that the previously severed web is dropped and jaws 51 and 52 are in position to engage the leading edge of the following packages containing goods 15.

At the end of forward stroke of carriage 12, roller arm on cam 31a is at the zenith of its circular path and engages cam lug 40 of lift bar 39 which, in turn, raises upper die 12a by means of hanger 37. Lower pressure plate 19 then elevates goods 15 to the level of pedestals 17 and 18 so smooth exiting of goods 15 from between upper and lower dies 12a. and 12b is assured. Just before carriage 12 starts its return motion, lug 68 engages arm 64- of preheat-sealing mechanism 60 disengaging indexing ball 66 from detent 67 and dropping heat-sealing rollers 60a into engagement with lower rollers 60b. Since webs 13a and 13b are stationary while carriage 12 (including preheat-sealing mechanism 60) is moving rearwardly, side seals on the two webs are provided. Near the end of the return stroke, lug 69 engages arm 64 and returns upper heat-sealing rollers 60a to a position spaced from lower rollers 60b.

During forward motion, a corrugated centrally-disposed longitudinal portion on lower web 13b is provided, by corrugating rolls 70 and 14b as previously described.

It is therefore'to be appreciated that my machine can be easily adapted to variations in heat scalability of the webs employed since the duration of heat-sealing can be readily altered. Also since my machine employs the webs 9 themselves for the enclosure to be evacuated, forming as well as evacuating the packaged goods, the costly evacuation chamber provided with internal heat-sealing equipment is eliminated.

It is to be appreciated that an alternative package canbe provided employing the machine and procedure of my invention wherein a film or web is folded longitudinally on itself and subsequently goods have been closed are provided with one longitudinal seal. I

The foregoing detailed description has been provided for clearness of understanding only and no unnecessary limitations are to be inferred therefrom.

I claim:

1. A packaging machine comprising a frame, a work holder slidably mounted on said frame, oscillating means associated with said frame for reciprocably moving said work holder, support means associated with said oscillating means and disposed parallel to and spaced from the sliding surface of said work holder, and a heat'sealing platen effective to. seal only on the forward stroke of said work holder associated with said work holder, said platen being borne by said holder on the forward stroke of said reciprocal motion, said platen being provided with hanger means engageable with said support means for supporting said platen spaced from said work holder on the return stroke of said reciprocal motion.

2. A packaging machine for encasing goods within a pair of parallel webs of heat-sealable material comprising a frame, a goods holder slidably mounted on said frame,

guide means associated with said holder disposed perpendicularly to the sliding surface thereof and spaced therefrom, a heat-sealing platen slidably associated with said guide means and borne by said holder, oscillating means for reciprocating said holder and platen assembly, platen lifting means associated with said oscillating means, and support means associated with said oscillating means to intermittently support said platen spaced from said holder whereby said platen and said holder are adapted to longitudinally and transversely heat-seal said webs together about encased goods only during a forward stroke and are adapted to permit removal of said goods during a return stroke.

3. A packaging machine of the character set forth in claim 2 wherein clamp means is mounted on said frame for clamping in tension said heat-sealed webs wherever said platen is spaced from said holder and means for cutting said heat-sealed webs is associated with and actuated by said oscillating means whenever said platen is borne by said holder.

4. A packaging machine comprising a frame, a goods carriage slidably mounted on said frame, said carriage comprising a goods holder and a heat-sealing platen arranged to press goods inserted therebetween, hanger means associated with said platen, a crank-actuated lever pivotally mounted at one end thereof on said frame and connected at an intermediate portion thereof with said carriage whereby crank rotation reciprocates said carriage, support means actuated from said lever and spaced above said platen hanger means, lift means associated with said lever and actuatable by said crank to raise said hanger means into supporting engagement with said support means, and disengagement means on said lift means for disengaging said hanger means from supporting engagement with said support means.

5. A packaging machine comprising a frame, a track on said frame, a goods carriage slidably mounted on said track, said carriage comprising a goods holder and a heat-sealing platen arranged to press goods inserted therebetween, hanger means secured to said platen on the side thereof opposite said holder, a crank-actuated lever pivotably mounted at one end thereof on said frame and connected at an intermediate portion thereof with said carriage whereby crank rotation reciprocates said carriage, a support bar pivotally secured to the unpivoted end of said lever and supported in spaced, parallel relation to said track, a lift bar pivotally secured to said lever coaxially with said support bar, cam means on said crank for engaging said lift bar upon the end of a carriage forward stroke to raise said lift bar into parallel, adjacent relation to said supported bar, said lift bar engaging said hanger means upon cam engagement to raise said hanger means into supporting engagement with said support bar, said lift bar beingprovided with disengagement means for disengaging said hanger from supporting engagement with said support bar upon the end of a carriage return stroke whereby goods are pressed between said holder and said platen only 'during said forward stroke.

6. A machine of the character set forth in claim 5 wherein the said lever is slidingly pivoted to crank means whereby the time duration of the forward carriage stroke is materially longer than the return stroke.

, 7. A machine of the character set forth in claim 5 wherein the platen is provided with a depending peripheral heat-sealing wall to form a goods-receiving chamber.

8. A machine of the character set forth in claim 7 wherein clamp means is mounted on said frame adjacent said lever, said clamp means being adapted to clamp in tension during said return stroke a heat-sealed web formed from a plurality of webs inserted between said platen and said holder whereby said carriage is returnable without injury to said web.

9. A machine of the character set forth in claim 8 wherein a lower web supply means is associated with said frame and so disposed therewith as to provide a horizontal length of web on the side of said carriage opposite said clamp means sufiicient to receive goods to be packaged when said carriage begins its forward stroke.

10. A machine of the character set forth in claim 8 wherein opposed, spaced pairs of heat-sealing elements are mounted on the end of said carriage opposite the end adjacent said clamping means, said elements being engageable into position by said support bar only during the return stroke of said carriage whereby preliminary side seals are provided on said webs.

11. A packaging machine comprising a frame, a work holder slidably mounted on said frame, oscillating means associated with said frame for reciprocably moving said work holder, support means associated with said oscillating means and disposed parallel to and spaced from the sliding surface of said work holder, and a heat-sealing platen associated with said work holder, said platen being home by said holder on the forward stroke of said reciprocal motion in heat-sealing relation with the web material positioned therebetween, said platen being provided with hanger means engageable with said support means for supporting said platen spaced from said work holder on the return stroke of said reciprocal motion whereby scaling is limited to said forward stroke, said heat-sealing platen having a depending wall defining the goods to be packaged and carrying heat-sealing means, a portion of said wall being reciprocably associated with said platen, a second depending wall portion on said platen parallel to said reciprocably associated portion, said second wall and the unreciprocal portion of said first-mentioned depending wall defining an elongated chamber for the goods to be packaged, an evacuating conduit mounted on said frame and extending athwart said second depending wall but terminating short of said reciprocably associated portion.

12. A machine of the character set forth in claim 11 wherein said support means actuates said reciprocably associated wall portion into engagement with said Work holder during a later portion of the forward stroke of said reciprocal motion.

13. A claim of the character set forth in claim 12 wherein heated corrugating roll means are associated with said frame and actuatable by said work holder to corrugate a portion of a web carried by said work hold er undersaid evacuating conduit.

14. A packaging machine comprising a frame, a goods carriage ,slidably mounted on said frame, said carriage comprising a goods holder and a heat-sealing platen arranged to press goods inserted therebetween, said heatsealing platen having a depending wall deferring the goods to be packaged and carrying heat-sealing means, a portion of said wall being reciproeably associated with said platen, a second depending wall portion on said platen parallel to said reciprocably associated portion, said second wall and the remainder of said depending wall defining an elongated chamber for the goods to be packaged, an evacuating conduit mounted on said frame and extending athwart said second depending wall but terminating short of said reciprocably associated portion, hanger means associated with said platen, a crank-actuated lever pivotally mounted at one end thereof on said frame and connected at an intermediate portion thereof with said carriage whereby crank rotation reciprocates said carriage, support means associated with the unpivoted end of said lever and spaced above said platen hanger means, lift means associated with said lever and 12 actuable by said crank to raise said hanger means into supporting engagement with said support means, and dis- 1 engagement means on said lift means for disengaging said hanger means from supporting engagement with said support means, said support means actuating said reciprocably associated Wall portion into engagement with said work holder during only a portion of the reciprocation of said Work holder.

References Cited in the file of this patent UNITED STATES PATENTS 1,899,207 Munson Feb. 28, 1933 2,116,995 Bickford May 10, 1938 2,160,367 Maxfield May 30, 1939 2,265,253 Smith Dec. 9, 1941 2,555,758 Noble et a1. June 5, 1951 2,606,412 Salfisberg Aug. 12, 1952 2,626,494 Lewis Jan. 27, 1953 2,696,562 Marks et al. Sept. 2, 1953 2,712,208 Campbell July 5, 1955 2,753,671 De Puy et a1. July 10, 1956 UNITED STATES PATENT OFFICE CERTIFICATION OF CORRECTION Patent N0a 3 011394 December 5 1961 Frank Jo P'ancratz It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below. v

Column 8,, line 31 after "estahlisheda" insert the following as a new paragraph: 1

- After approximately one-half forward travel of carriage 12 lug 48 depresses heat sealer element to provide the fourth side seal ongthe package which has been evacuated through evacuating tube 278 As. crank 31 continues its rotation and carriage l2 retuurns lug 4L9 depresses shear hlade 29 severing a pair of webs 13a and 13b previously heat-sealed togethers Signed and sealed this 17th day of April 19626 SEAL) Attestz- ESTQN c, JQHNSON Attesting Officer DAVID La LADD Commissioner of Patents 

